Oil lamp and methods of using the same

ABSTRACT

The present discussion generally describes a liquid fuel burning device such as an oil lamp having a reservoir for holding the liquid fuel and a flange substantially covering the liquid fuel holding area of the reservoir. The flange is sized and located to provide an opening between a perimeter of the flange and an inner surface of the reservoir. The opening permits a level of the liquid fuel to be monitored and/or checked during filling of the reservoir. Thus, the chance of having an overflow of liquid fuel or an under-filled reservoir is substantially reduced. The flange is configured with a downward slope to allow liquid fuel to drain toward the opening, if liquid fuel gets on the flange during filling of the device.

BACKGROUND OF THE INVENTION

1. Technical Field

This disclosure is generally related to a lamp device that burns a combustible substance by drawing the substance up through a wick, for example an oil lamp.

2. Description of the Related Art

Candles, gel pots, and oil lamps are commonly used as decorative light sources and can also be used to disperse fragrances. These light sources typically produce a yellow flame by burning a combustible substance (e.g., wax, gel, oil, etc.), which is continuously drawn up through a wick by capillary action. In the case when a wax or gel is used as the combustible substance, the heat of flame melts a small pool of the wax in the vicinity of the wick stem to allow the melted wax to be drawn up through the wick.

Unlike candles or gel pots, the oil in an oil lamp is already in a liquid state and does not need to be heated by the flame to invoke capillary action. The liquid form of the oil, however, makes an oil lamp more susceptible to spillage of the oil either during use or during refilling of the oil. Typically, the oil is held in a container and the only access to the oil is through the wick. A cover over the oil acts as barrier to prevent the flame from igniting the oil held in the container. The cover can be removable from or integral with the container.

When the cover and container are integral, the process of filling or refilling an opaque (i.e., non-glass or non-transparent) oil lamp requires at least that the flame be temporarily extinguished and the wick removed. The wick is removed and oil is added into the container through the wick aperture, which often requires the use of a small or specialized funnel which is often misplaced or lost. Where the cover is removable, the flame must still be extinguished before refilling to prevent the oil in the container from igniting.

A common purpose of oil lamps is to disperse fragrance molecules into the air. However, when the lamp is covered or when the container and cover are integral, the dispersal of fragrance molecules into the air is significantly restricted, if not nonexistent. Some devices propose to disperse the fragrance molecules through the wick. But, the fragrance molecules are usually destroyed or significantly altered when the oil is drawn up through the wick and burned by the flame. The combustion process tends to produce a “fuel” or “burnt” smell instead of the desired odor of the fragrance.

One approach to an oil lamp that emits a fragrance when ignited is disclosed in U.S. Pat. No. 6,555,069, issued to Ferguson, in which the oil lamp includes a ceramic diffuser. The ceramic diffuser of the '069 patent functions as a secure top, absorbs some of the oil, and releases the absorbed oil into the surrounding air. A drawback is that this type of oil lamp still requires that the flame be extinguished and the top removed before more oil can be added to the container.

Consequently, there remains a need to maintain the oil securely in the oil lamp, allow a sufficient number of fragrance molecules to be dispersed into the air while the oil lamp is burning, protect the oil from the open flame, and provide a means to easily fill and refill the oil lamp with a reduced risk of underfill, overflow, or leakage. Further, the filling and refilling of the oil lamp should be easy and quick without the need for specialized funnels or tubes to get the oil into the container.

SUMMARY OF THE INVENTION

In one aspect of the invention, a liquid-fueled lamp includes a reservoir to hold liquid fuel, the reservoir having an outer surface and an inner surface; a wick holder supported within the reservoir; a flange coupled with the wick holder, the flange configured with a downward slope directed from the wick holder toward the inner surface of the reservoir; and an opening located between a perimeter of the flange and the inner surface of the reservoir, the opening sized to provide a visual indication of a fuel level of the liquid fuel in the reservoir.

In another aspect of the invention, a lamp includes a reservoir comprising a wall having an interior surface and an exterior surface, the interior surface forming a reservoir for receiving a liquid fuel, the reservoir open at one end thereof and closed at an opposite end; a wick holder received in the reservoir and coupled to the reservoir, the wick holder forming at least one passage for supportably receiving a wick; a flange extending from the wick holder toward the interior surface, the flange having a perimeter, the perimeter being spaced from the interior surface to form a gap therebetween.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, identical reference numbers identify similar elements or acts. The sizes and relative positions of elements in the drawings are not necessarily drawn to scale. For example, the shapes of various elements and angles are not drawn to scale, and some of these elements are arbitrarily enlarged and positioned to improve drawing legibility. Further, the particular shapes of the elements as drawn, are not intended to convey any information regarding the actual shape of the particular elements, and have been solely selected for ease of recognition in the drawings.

FIG. 1 is a front, left isometric view of a lamp for receiving, holding, and burning liquid fuel such as oil according to one illustrated embodiment.

FIG. 2A is a cross sectional view of the device of FIG. 1 with a wick holder coupled to a reservoir according to one illustrated embodiment.

FIG. 2B is a cross sectional view of a wick holder mechanically coupled to a reservoir according to another illustrated embodiment.

FIG. 2C is a cross sectional view of a lamp having a truncated wick holder according to another illustrated embodiment.

FIG. 3 is front, right isometric view of a wick holder according to one illustrated embodiment.

DETAILED DESCRIPTION OF THE INVENTION

In the following description, certain specific details are set forth in order to provide a thorough understanding of various embodiments of the invention. However, one skilled in the art will understand that the invention may be practiced without these details. In other instances, well-known structures associated with lamps (e.g., oil lamps), lanterns, camping stoves, wicks, and other similar devices may not be shown or described in detail to avoid unnecessarily obscuring descriptions of the embodiments of the invention.

Unless the context requires otherwise, throughout the specification and claims which follow, the word “comprise” and variations thereof, such as, “comprises” and “comprising” are to be construed in an open, inclusive sense, that is as “including, but not limited to.”

The headings provided herein are for convenience only and do not interpret the scope or meaning of the claimed invention.

FIG. 1 shows an oil lamp 10 having a reservoir 12 and a lid 14 according to one illustrated embodiment. The reservoir 12 is bowl shaped with an inner surface 12 a and an outer surface 12 b. The inner surface 12 a forms a reservoir to receive fuel, for example a liquid fuel such as oil (with or without fragrance), citronella (lemon odor), citronellol (rose-like odor), or any other like fuel that is slow burning and permissible in a liquid-fueled lamp. The reservoir 12 has a rim 12 c that forms an opening to at an upper end thereof to receive liquid fuel. A flange 16 and a wick holder 18 are positioned within the reservoir 12. The reservoir 12 can be made out of metal (e.g., stainless steel, aluminum, bronze, copper, etc.), ceramic, or some other flame resistant, opaque material. The lid 14 and the flange 16 can be made out of the same or an equivalent material. In the illustrated embodiment, the reservoir 12, lid 14, and flange 16 are made out of stainless steel and the wick holder 18 is made from bronze. It is appreciated and understood that the reservoir 12, the lid 14, flange 16, and wick holder 18 can vary in size and shape and the illustrated configuration is exemplary.

The lid 14 may include a decorative handle 14 a to allow for easy removal and replacement of the lid 14. When the oil lamp 10 is lit, the lid 14 can be used to cover the reservoir 12 and wick holder 18 to substantially starve the flame for oxygen and ultimately extinguish the flame. In addition, leaving the lid 14 on when the oil lamp 10 is not in operation helps keep the oil from evaporating.

FIG. 2A shows the reservoir 12 of the oil lamp 10 with oil 20 that is filled to an oil level 20 a. In the illustrated embodiment, the reservoir 12 is approximately semi-hemispherical and configured with a substantially flat bottom surface 22, which permits the oil lamp 10 to be placed in a stable configuration on a flat surface such as a coffee table, counter top, or shelf, for example. Alternatively, the oil lamp 10 may be supported by a holder such as a wrought iron base, for example.

The wick holder 18 is supported on the inner surface 12 a of the reservoir 12. Although the wick holder 18 can simply rest on the inner surface 12 a, such would not be as desirable as a wick holder 18 that is held stationary in the reservoir 12. In the illustrated embodiment, the wick holder 18 is mechanically coupled with the reservoir 12 to keep the wick holder 18 at least temporarily fixed. There are a variety ways to fixedly or removably mechanical couple the wick holder 18 to the reservoir 12, for example by complementary threads, complementary clipping elements, etc.

The wick holder 18 includes a first protuberance 24 that complementarily recesses into a clip 26 extending from the reservoir 12. The wick holder 18 can be snapped or twisted into place. In an alternate embodiment shown in FIG. 2B, the wick holder 18 and an inner ring 28 are configured with complementary, helical threads that permits the wick holder 18 to selectively be rotationally engaged and disengaged from the reservoir 12.

Referring back to FIG. 2A, the wick holder 18 further includes a second protuberance 30. The second protuberance 30 supports the flange 16. The flange 16 is provided with an opening 16 a sized to fit around the perimeter of the wick holder 18 while not sliding down over the second protuberance 30.

In FIGS. 2A and 2C, the flange 16 has a first height “A” and a second height “B,” both relative to the bottom surface 22 of the reservoir 12. The first height “A” is greater than the second height “B,” which means that the flange 16 is configured to slope downward from its support location on the wick holder 18 toward the inner surface 12 a of the reservoir 12. As shown in the illustrated embodiment, the flange 16 may even have a slight, concave curvature. The downward slope, with or without the curvature, encourages oil that is spilled onto or otherwise contacts the flange 16 to run off the flange and into the reservoir 12.

The flange 16 further includes an outer perimeter 16 b sized to fit within the reservoir 12. In one embodiment, a cross-sectional area of the reservoir 12, taken parallel to the horizontal, may continually increase as one follows the contour of the inner surface 12 a of the reservoir 12 upward. One skilled in the art will appreciate and understand that cross-sectional area of the reservoir 12 increases exponentially as a function of the diameter (d) of the inner surface 12 a (area=π*d²/4). The outer perimeter 16 b of the flange 16 is sized to form an opening or gap 32 with respect to the inner surface 12 a of the reservoir 12. Thus, the flange 16 will have a smaller radius and outer perimeter 16 b where the flange 16 is situated at a low elevation in the reservoir 12, while the flange 16 will have a larger radius and outer perimeter 16 b where the flange 16 is situated at a high elevation in the reservoir 12. In any case, the outer perimeter 16 b of the flange 16 is smaller than the perimeter of the inner surface 12 a of the reservoir 12 at a location on the inner surface 12 a opposed to the outer perimeter 16 b. The gap 32 is large enough to receive the oil 20 during the filling or refilling process without causing the oil 20 to substantially back-up when the oil 20 is poured into the reservoir 12 at reasonable rate. In one embodiment, the oil 20 is poured directly onto the flange 16, but away from the wick holder 18, where the oil 20 then runs down the flange 16, through the gap 32, and into the reservoir 12.

FIG. 2C illustrates an alternate embodiment in which an upper edge 18 a of the wick holder 18 is flush with an inner portion 16 c of the flange 16. In other words, the wick holder 18 is truncated to be flush with the inner portion 16 c of the flange 16.

One advantage of the gap 32 is that it allows the level 20 a of the oil 20 to be observed during the filling/refilling process without removing the wick 34 or any associated components. It should be understood that the level 20 a may not be visible at all times during the refilling process, but as the level 20 a increases, the level 20 a will become observable through the gap 32 to a user pouring oil 20 into the oil lamp 10. In addition, due to the increasing cross-sectional area of the reservoir 12, as described above, the fill rate (i.e., the rate at which the level 20 a rises within the reservoir 12) actually decreases as long as a volumetric input rate of the oil 20 being added remains substantially constant during the filling or refilling process. Hence, a user can refill the reservoir by adding oil 20 at a relatively constant rate with much less concern that the oil 20 will suddenly overflow the rim 12 c of the reservoir 12. In short, observing the oil level 20 a through the gap 32 during the filling or refilling process significantly reduces the risk of both overflowing and under filling the reservoir 12.

Another advantage is that the gap 32 provides a region around the flange 16 where the fragrance molecules of the oil 20 can be directly dispersed into the air. This eliminates the need for special diffusers or other devices.

Yet another advantage is that the gap 32 permits the reservoir 12 to be filled without removing the wick and/or without special tools.

FIG. 3 shows the wick holder 18 with wick material 34 placed in the wick holder 18. The wick holder 18 includes a plurality of openings 36 to receive the oil 20 in the reservoir 12. As previously discussed, the oil 20 wets the wicking material 34 through capillary action. The openings 36 can be located and spaced around the bottom portion of the wick holder 18 or can be formed in the wick holder 18 slightly above the bottom region. The openings 36 can also correspond and align with any openings that are formed in the clips 26 or inner ring 28 used to secure the wick holder with the reservoir 12, as discussed above and illustrated in FIGS. 2A, 2B, and 2C.

Although specific embodiments of and examples for the oil lamp and method of filling the oil lamp are described herein for illustrative purposes, various equivalent modifications can be made without departing from the spirit and scope of the invention, as will be recognized by those skilled in the relevant art. The teachings can apply to any type of oil lamp or other lamp, lantern, or device that uses a combustible liquid for fuel. Additionally, any method described above may include additional steps, omit some steps, and perform some steps in a different order than illustrated and/or otherwise described.

The various embodiments described above can be combined to provide further embodiments. All of the above U.S. patents, patent applications and publications referred to in this specification are incorporated herein by reference. Aspects of the invention can be modified, if necessary, to employ devices, features, and concepts of the various patents, applications and publications to provide yet further embodiments of the invention.

These and other changes can be made to the invention in light of the above detailed description. In general, in the following claims, the terms used should not be construed to limit the invention to the specific embodiments disclosed in the specification and the claims, but should be construed to include all reusable card configurations and methods that operate in accordance with the claims. Accordingly, the invention is not limited by the disclosure, but instead its scope is to be determined entirely by the following claims. 

1. A liquid-fueled lamp, comprising: a reservoir to hold liquid fuel, the reservoir having an outer surface and an inner surface; a wick holder supported within the reservoir; a flange coupled with the wick holder, the flange configured with a downward slope directed from the wick holder toward the inner surface of the reservoir; and an opening located between a perimeter of the flange and the inner surface of the reservoir, the opening sized to provide a visual indication of a fuel level of the liquid fuel in the reservoir.
 2. The liquid-fueled lamp of claim 1, further comprising: a lid to cover the reservoir.
 3. The liquid-fueled lamp of claim 1, further comprising: wick material located within the wick holder.
 4. The liquid-fueled lamp of claim 1 wherein the reservoir is configured with a substantially flat bottom portion.
 5. The liquid-fueled lamp of claim 1, further comprising: an amount of oil received in the reservoir.
 6. The liquid-fueled lamp of claim 1 wherein the wick holder includes a protuberance.
 7. The liquid-fueled lamp of claim 6 wherein the flange coupled with the wick holder includes the flange being supported on the protuberance of the wick holder.
 8. The liquid-fueled lamp of claim 1 wherein the downward slope of the flange is sufficient to permit at least some liquid on top of the flange to drain toward the opening.
 9. The liquid-fueled lamp of claim 1 wherein the visual indication of the fuel level of the liquid fuel in the reservoir is obtained without manipulation of the flange.
 10. A lamp, comprising: a reservoir comprising a wall having an interior surface and an exterior surface, the interior surface forming a reservoir for receiving a liquid fuel, the reservoir open at one end thereof and closed at an opposite end; a wick holder received in the reservoir and coupled to the reservoir, the wick holder forming at least one passage for supportably receiving a wick; and a flange extending from the wick holder toward the interior surface, the flange having a perimeter, the perimeter being spaced from the interior surface to form a gap therebetween.
 11. The lamp of claim 10 wherein the reservoir is approximately circular.
 12. The lamp of claim 10 wherein the reservoir has an approximately flat base.
 13. The lamp of claim 10 wherein the flange is spaced below the top of the reservoir.
 14. The lamp of claim 10 wherein the top of the wick holder is spaced below the top of the reservoir.
 15. The lamp of claim 10 wherein the wick holder is an elongated cylinder and the passage is a longitudinally extending passage. 